1. Field of the Invention
The present invention relates to a connector contained in electronic equipment, and more particularly to an external memory pack connector which electrically and physically connects an external memory pack containing a memory element such as ROM or RAM and a main body of electronic equipment.
2. Description of the Prior Art
In the past, connection of a connector of electronic equipment and an external memory pack has been usually made by inserting terminals of a printed circuit board of the external memory pack into the connector or urging them to an outer case. However, in the former case, there is a problem in durability, and in the latter case, a portion of the outer case is deformed by pressure of the contacts and sufficient contact pressure is not obtained. Further, in both cases, the operability by a user is very poor.
In Figs. lA, lB, lC, 2 and 3, numeral 101 denotes a connector body, numeral 102 denotes an insertion port into which an external memory pack 10 is inserted, numeral 104 denotes connector contacts to be contacted to the external memory pack 10, and numeral 103 denotes an external memory pack removal lever by which the external memory pack 10 inserted into the insertion port 102 is removed.
FIGS. 2 and 3 show sectional views of the connector of FIG. 1 and show internal structures thereof. In FIG. 2, the external memory pack 10 is not inserted. The connector contacts 104 have constant spring forces to flex them in a direction B. The removal lever 103 has a projection 107 with which tip ends of the connector contacts 104 engage. Thus, the removal lever 103 tends to be rotated by the spring forces of the connector contacts 104 in a direction C around a pivot point 103A. Numeral 105 denotes a vertically movable platform which is urged toward the removal lever 103 by a leaf spring 106. The movable platform 105 has a projection 109 with which an end of the removal lever 103 engages. The rotation of the removal lever 103 in the direction C is suppressed by this engagement. Thus, the spring forces of the connector contacts 104 in the direction B are suppressed by the engagement of the removal lever 3 by the projection 109. Thus, the position shown in FIG. 2 is maintained stably.
Let us assume that the external memory pack 10 is inserted into the insertion port 102 in a direction D. As the external memory pack 10 is inserted into the insertion port 102 and the movable platform 105 is moved down to a position at which the removal lever 103 and the projection 109 of the movable platform 105 are disengaged from each other, the removal lever 103 is rotated in the direction C by the spring pressures of the connector contacts 104 in the direction B so that the removal lever 103 slips onto the top 108 of the movable platform 105 to prevent the lifting of the movable platform 105. The connector contacts 104 are flexed in the direction B and contacts to the contact pattern 10A of the external memory pack 10. This position is shown in FIG. 3.
The removal operation of the external memory pack 10 is now explained. In FIG. 3, as the removal lever 103 is rotated in the direction A (this operation requires a force larger than a predetermined force because it is against the spring forces of the connector contacts 04), the connector contacts 104 are urged oppositely to the direction B by the projection 107 of the removal lever 103, and the contact pattern 10A of the external memory pack 10 and the connector contacts 104 are disengaged from each other. As the removal lever 103 is rotated in the direction A and disengaged from the top 108 of the movable platform 105, the movable platform 105 is lifted by the leaf spring 106 and pushes up the external memory pack 10 and the projection 109 of the movable platform 105 again engages with the removal lever 103. As a result, the rotation of the removal lever 103 in the direction C by the spring pressures is inhibited. Thus, the position before the insertion of the external memory pack is restored.
In such a prior art connector, if an operator advertently or inadvertently removes the inserted external memory pack 10 during the access to it by the equipment, it leads to the destruction of the program and breakage of the connector contacts 104 because the connector contacts 104 are press-contacted to the contact pattern 10A of the external memory pack 10.
Further detail will be explained with reference FIGS. 4A to 4C and 5A to 5C. FIGS. 4A, 4B, and 4C are respectively a top view, front view and side view of the connector. Numeral 201 denotes a connector body, numeral 202 denotes an insertion port for the external memory pack 10 and which is shaped to fit the external memory pack 10, and numeral 203 denotes connector contacts.
FIGS. 5A, 5B and 5C show sectional views of the connector taken along a line 5A--5A in FIG. 4A. FIG. 5A shows a contact position in which the contacts 203 project into the insertion port 202, FIG. 5B shows a non-contact position, and FIG. 5C shows a position in which the external memory pack 10 is inserted.
The contacts 203 have spring pressures which normally flex the contacts 203 in a direction a. Because of the contact pressure afforded by the spring forces, the stable contact is maintained. Numeral 204 denotes a lever which is rotated around a pivot point 210. Terminals of the contacts 203 engage with a tip end 206 of the lever 204. The lever 204 tends to be rotated oppositely to the direction A by the spring forces of the contacts 203, but it is held in the position shown in FIG. 5A by a projection 207 on an upwardly and downwardly movable platform 205.
When the external memory pack 10 is to be inserted into the connector, the lever 204 is manually rotated in the direction A. As the lever 204 is rotated, the movable platform 205 is moved in the direction B by the leaf spring 208 and it is lifted to the position shown in FIG. 5B. Even if the lever 204 is no longer rotated in the direction A, the lever 204 is secured by the sloped surface of the movable platform 205 so that it is not returned to the position of FIG. 5A by the spring forces of the contacts 203 and is held at the position of FIG. 5B. At this time, the contacts 203 do not project into the insertion port 202 and are in the non-contact position.
As the external memory pack 10 is inserted from the insertion port 202 and the movable platform 205 is pushed down in the direction C against the spring force of the leaf spring 208, the lever 204 is disengaged from the sloped surface 209 of the movable platform 205 and rotated by the spring forces of the contacts 203 in the direction D around the pivot point 210. The contacts 203 project from the insertion port 202 and put in the contact position. This is shown in FIG. 5C.
However, in order to rotate the lever 204 of the connector in the direction A, it must be rotated against the spring forces of the contacts 203 and the load thereof is usually larger than 5 Kg. Thus, the operation is very difficult. It is not possible to automatically operate the lever without intervention of the operator.